[ihavenofish]

datron machines start at about 60k. just sayin

they are also light weight gantry routers build on a granite plate. not really in any way comparable to a cast iron mill of any size. they are build for speed and precision and not general purpose milling.

[tmarks11]

FEA mainly works with sheetmetal structures likely a brige or similar..
you can apply for cast iromn structures, but a real analysys will cost way more that customers of these machine ever could pay..

Nice try. "Sheet metal structures likely a bridge?" huh? Never seen a "sheet metal" bridge. Most bridges I see are either made out of steel girders or are reinforced concrete. No sheet metal in sight.

FEA excels for analysis of solid structures. How else do you think we design bridges, skyscrapers, and machinery in a modern world?

Good FEA software is expensive, but that is not the same thing as saying "FEA is unaffordable". Fully functional educational versions of the software can be obtained (assuming you qualify) if you don't have access to the registered versions. While not as capable as some (more expensive) FEA software, the educational (also available to veterans) Solid Works edition includes the full Simulation Premium package, allowing anyone with some ME background and solid modeling capability to conduct basic FEA of structures.

SOLIDWORKS Simulation Premium | SOLIDWORKS

[RCaffin]

A friend of mine has a medium-to-larger machine which relies on floating the table on high-pressure hydraulics. There may be Rulon or Torlon faces in there as well. Costs a small fortune just to power the machine up! So where does that fit in with or against rails and so on these days?

Cheers
Roger

[victorofga]

you can entering in details, however on the end it will comes back for this machine simply don't worth to looking for superprecision..
riding on words... you can do it.. it just about you changing subject..

with other words this machine made for folks who can afford only this.. and those folks are happy, don't complaining, but all others who never will buy one.. for all complainers, would nbe better just simply post a full documentation how yours would looking for this money..
with dimensions with materials and everything..

unless you show solution complaining itself on things... it lead no where..

[aarggh]

this machine what visible built for general works, jobs these concerning just like one try to buying a wooden handle for showel, and checking with micrometer...

what would you all say, if were see someone in the lowes measuring a showel handle with micrometer?

Hit the nail on the head!

cheers, Ian

[louieatienza]

Nice try. "Sheet metal structures likely a bridge?" huh? Never seen a "sheet metal" bridge. Most bridges I see are either made out of steel girders or are reinforced concrete. No sheet metal in sight.

FEA excels for analysis of solid structures. How else do you think we design bridges, skyscrapers, and machinery in a modern world?

Good FEA software is expensive, but that is not the same thing as saying "FEA is unaffordable". Fully functional educational versions of the software can be obtained (assuming you qualify) if you don't have access to the registered versions. While not as capable as some (more expensive) FEA software, the educational (also available to veterans) Solid Works edition includes the full Simulation Premium package, allowing anyone with some ME background and solid modeling capability to conduct basic FEA of structures.

SOLIDWORKS Simulation Premium | SOLIDWORKS

To what end? First of all, I'm prettysure you can't use the educational versionfor commercial use, that would violate the EULA. So yes for a small startup commercial grade FEA may not be feasible since the ROI we could take months, years. And really in the grand scheme of things knowing the precision of every other component and the stated accuracy is it really needed? Or, maybe if Defeng made 5000 of these a year, it may be worthwhile as far as optimizing materials usage. But in this case, for a 220lb. machine, aimed at a target market, it it way more than adequate.

I can be sure of one thing - Grizzly, Sieg, LMS, as far as I know do NOT use FEA in their designs.

- - - Updated - - -

Hit the nail on the head!

cheers, Ian

Aye aye...

[RCaffin]

Mind you, I found the FEA diagrams/results interesting and educational.

Cheers
Roger

[tmarks11]

I can be sure of one thing - Grizzly, Sieg, LMS, as far as I know do NOT use FEA in their designs.

Mostly because they are just copying or adapting machinery that was designed before computers were invented.... even down to the "M" on the milling machine base...

My recommendation of educational software was aimed at the suggestion that a customer can dabble in FEA modeling of what he bought for the shear joy of it (which was what G59 said when he first showed his images of a wet noodle).

However, you can get a SW seat with the simulation plug-in for $12k. Not talking $100k here to get analysis done for someone who has a commercial interest.

Back OT, Defeng hasn't posted for 2.5 months. Hopefully things are still going well with him. I wonder how the Chinese Yuan devaluation is affecting him and his supply chain (Yes, I know it was "only" 4.4%)?

[RCaffin]

Hi Tmarks

Assume I am ignorant, and educate me: where does the 'M' come from - ie whose brand was it?

Does that mean some people have been taking sand molds off an old machine? Dear me.

Cheers
Roger

[ihavenofish]

Mostly because they are just copying or adapting machinery that was designed before computers were invented.... even down to the "M" on the milling machine base...

My recommendation of educational software was aimed at the suggestion that a customer can dabble in FEA modeling of what he bought for the shear joy of it (which was what G59 said when he first showed his images of a wet noodle).



However, you can get a SW seat with the simulation plug-in for $12k. Not talking $100k here to get analysis done for someone who has a commercial interest.

Back OT, Defeng hasn't posted for 2.5 months. Hopefully things are still going well with him. I wonder how the Chinese Yuan devaluation is affecting him and his supply chain (Yes, I know it was "only" 4.4%)?

the base package of solidworks at $4000 can do single object fea and is still very useful. there are many options that dont cost alot for fea. there is no reason to assume any chinese machine maker cant or wouldnt do fea on their original design machines.

[tmarks11]

Assume I am ignorant, and educate me: where does the 'M' come from - ie whose brand was it?

The molded in "M" on the mill meant that the Meehanite process was used in making of the casting. It is a trademark that appeared on US mills.

Meehanite: What's different about Meehanite

Story goes that the entire casting was copied by a chinese manufacturer... complete with the "M".... but they didn't actually know what the M stood for and didn't actually employ the process. Might be an apocryphal story.

[ihavenofish]

Hi Tmarks

Assume I am ignorant, and educate me: where does the 'M' come from - ie whose brand was it?

Does that mean some people have been taking sand molds off an old machine? Dear me.

Cheers
Roger

meehanite. its not so much a brand as a stamp of process adherence to get a specific iron composition.

so yeah, some of the machines are just recast of existing ones, and may include the M even though they arent licensed. others are actually licensed. hard to know for sure.

defengs machines are an entirely different procedure. just a basic "small part" grey iron casting. usually ht250 on small machines and ht350 on larger. they use the "lower" strength on small castings because its preferred in thinner castings. different irons develop strength based on cooling rate which is directly related to thickness. HT350 for example may become too hard and brittle on a 4-6mm thick wall, and ht250 wouldnt develop enough strength at 15-20mm..

[louieatienza]

Mostly because they are just copying or adapting machinery that was designed before computers were invented.... even down to the "M" on the milling machine base...

My recommendation of educational software was aimed at the suggestion that a customer can dabble in FEA modeling of what he bought for the shear joy of it (which was what G59 said when he first showed his images of a wet noodle).

However, you can get a SW seat with the simulation plug-in for $12k. Not talking $100k here to get analysis done for someone who has a commercial interest.

Back OT, Defeng hasn't posted for 2.5 months. Hopefully things are still going well with him. I wonder how the Chinese Yuan devaluation is affecting him and his supply chain (Yes, I know it was "only" 4.4%)?

Exactly. If you're making a copy of a proven design, why the need for FEA? For the joy of it? That's fine, but inot G59's case it was done to stick it to Mr.Handlewanker, and maybe discredit the work of Defeng. The reality is under its intended use and maybe more, this machine is not going to shake around like those blow up wavy things at the car wash. This is so obvious that it should not néedo mentioning, but soany hobbyists get consumed with FEA and not pay attention to other things (my aforementioned story of the guy who used FEA to design a mill of 2 x 4 lumber and sheet rock screws comes to mind.) If however we're designing the stiffest column using the least amount of material possible, thenot I can see the practicality.

Haven't had the opportunity to contact Defeng lately, I wish him well and hope the recent events haven't hurt him much if at all.

[daniellyall]

around and around we go just let lou get his up and going then he will say`s how good or bad it is then go from there If you don`t like what Ian says just let it go

[xjdubber]

the issue here is that the state of the art in cnc mechanicals hasnt changed much in nearly 40 years.

If you are refere to the basic idea and operation then yes, i would agree. However if you look at the precision and speed that machining can be achieved then i'd say a lot has changed in the last 40 years....

[G59]

Posting my quick and dirty FEA results was indeed in part to shut someone who I think deserved it.
To discredit the builder? Not my intention.

But the results speak for themselves and yes they look grossly exaggerated but purposely done by all FEA softwares so the results can be better assessed. It doesn't mean you'll ever come close to that amount of distortion in reality.
But really what matters is the resonance and at what Hz.
In machine tools, such as this mill, Frequency in hertzs X 60 seconds X number of flutes of an end mill(for example), = at what rpm you will have reached the resonant frequency. That's the rpm you should stay away from.
Surface finish is likely to suffer, however minute, if ignored.
As for FEA being expensive, well it came with Inventor Pro 2014 that we use at work. $7900 we'll spent.

Also, standard frequency range for designing machine tools is 0-2000Hz. This range covers 99.9% of the expected end use of the machine.

Anyways, it's been an interesting read about sub micron and glass scales etc....
I think though that's a bit too much for hobbyists. As stated earlier, it drives the price up considerably.

[daniellyall]

G59 you can use the ignore list.

[louieatienza]

Posting my quick and dirty FEA results was indeed in part to shut someone who I think deserved it.
To discredit the builder? Not my intention.

But the results speak for themselves and yes they look grossly exaggerated but purposely done by all FEA softwares so the results can be better assessed. It doesn't mean you'll ever come close to that amount of distortion in reality.
But really what matters is the resonance and at what Hz.
In machine tools, such as this mill, Frequency in hertzs X 60 seconds X number of flutes of an end mill(for example), = at what rpm you will have reached the resonant frequency. That's the rpm you should stay away from.
Surface finish is likely to suffer, however minute, if ignored.
As for FEA being expensive, well it came with Inventor Pro 2014 that we use at work. $7900 we'll spent.

Also, standard frequency range for designing machine tools is 0-2000Hz. This range covers 99.9% of the expected end use of the machine.

Anyways, it's been an interesting read about sub micron and glass scales etc....
I think though that's a bit too much for hobbyists. As stated earlier, it drives the price up considerably.

I tend to wonder. Intentional or not. You came here and criticized this machine from the start. I'm sure Ian doesn't intend to be dead wrong about many things either. Again that FEA is useless if you just model it alone. The 30lb head acts as a ballast and mitigates some vibration and shortens the effective column length, even the ball bearings in the LM blocks act as dampers.

Nowadays servos are becoming cheaper and entering the hobby level more, so it may not be too long before we see linear encoders for the home shop.

[ihavenofish]

magnetic linear encoders can be had for $50 an axis in parts, repeatable resolution to half micron, true precision to 10-20 microns (not counting mechanical factors on the machine itself).

i dont think any of our low costs controls make good use of them though.... yet.

[bhurts]

Do you have a link to a supplier for the linear encoders? I have seen the ones from us digital and they are limited to 35.5 inches max length. If you know of something at the price you mentioned that can reach at least 120 inches or around 3 meters I'd love to hear about it.

Ben